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span{color:var(--color-text);font-weight:700}.eq-bar{width:100%;max-width:320px}.eq-bar-track{background:var(--color-border-light);border-radius:var(--radius);height:28px;position:relative;overflow:hidden}.eq-bar-fill{border-radius:var(--radius);height:100%;position:absolute;top:0;left:0}.eq-bar-fill--base{background:var(--color-primary);opacity:.25}.eq-bar-fill--add{background:var(--color-accent-green);opacity:.7}.eq-bar-fill--sub{background:var(--color-accent-red);opacity:.7}.eq-bar-labels{color:var(--color-text);font-size:11px;font-weight:600;font-family:var(--font-figure);justify-content:space-between;margin-top:4px;display:flex}.eq-explain-footer{justify-content:center;gap:12px;margin-top:20px;display:flex}.eq-btn--gotit{background:var(--color-surface);color:var(--color-text);border:1.5px solid var(--color-border-dark);min-height:44px;padding:8px 24px;font-size:14px}.eq-btn--gotit:hover{background:var(--color-surface-hover)}.eq-btn--replay{border:1.5px solid var(--color-border-dark);min-height:44px;color:var(--color-text);cursor:pointer;border-radius:var(--radius);background:0 0;padding:6px 14px;font-family:inherit;font-size:13px;font-weight:600;transition:background-color .15s,border-color .15s,color .15s}.eq-btn--replay:hover{background:var(--color-surface-hover);color:var(--color-text)}@media (width<=768px){.eq-explorer{gap:16px}.eq-controls{gap:8px}.eq-board{flex-wrap:wrap;gap:4px;padding:24px 4px}.eq-term{font-size:32px}.eq-tile{border-radius:var(--radius);min-width:52px;height:56px;padding:0 10px}.eq-blank{border-radius:var(--radius);width:62px;height:56px;font-size:32px}.eq-op{min-width:22px;font-size:24px}.eq-equals{font-size:28px}.eq-btn{min-height:44px;padding:12px 22px;font-size:15px}.eq-explain-inner{padding:16px}.eq-tenframe-grid{gap:5px;max-width:220px}.eq-explain-tab{justify-content:center;align-items:center;min-height:44px;display:flex}.eq-btn--replay,.eq-btn--gotit{min-height:44px}}@media (width<=380px){.eq-term{font-size:28px}.eq-tile{min-width:46px;height:50px;padding:0 8px}.eq-blank{width:54px;height:50px;font-size:28px}.eq-op{min-width:18px;font-size:22px}.eq-equals{font-size:24px}.eq-side{gap:4px;padding:6px}.eq-controls{flex-direction:column;align-items:stretch}.eq-controls .btn-group{width:100%}.eq-controls .btn-toggle{flex:1;min-height:44px}}@media (prefers-reduced-motion:reduce){.eq-confetti,.eq-checkmark,.eq-op-symbol--enter,.eq-tenframe-dot--add,.eq-tenframe-dot--remove,.eq-explain,.eq-blank--wrong{animation:none}}.eq-numpad{--_key:clamp(48px, calc((100dvh - 400px) / 5), 100px);background:var(--cover);border-radius:var(--radius);flex-direction:column;align-items:center;width:fit-content;margin:12px auto 0;padding:10px;display:flex}.eq-numpad-digits{grid-template-columns:repeat(3, var(--_key));gap:8px;display:grid}.eq-numpad-key{aspect-ratio:1;font-size:clamp(20px, calc(var(--_key) * .38), 32px);border-radius:var(--radius);background:var(--paper);color:var(--color-text);cursor:pointer;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent;box-shadow:0 0 0 1px var(--edge), var(--shadow-sm);border:none;font-weight:600;transition:background .1s,transform 80ms,box-shadow .1s}.eq-numpad-key:active{background:var(--paper-edge);transform:scale(.94);box-shadow:0 0 1px #1a1f241f}.eq-numpad-key--muted{background:var(--paper-edge);font-size:clamp(16px, calc(var(--_key) * .3), 26px);box-shadow:none}.eq-numpad-key--muted:active{background:var(--color-border)}.eq-numpad-action{width:calc(var(--_key) * 3 + 16px);height:calc(var(--_key) * .55);min-height:36px;font-size:clamp(14px, calc(var(--_key) * .22), 20px);letter-spacing:.02em;border-radius:var(--radius);background:var(--color-primary);color:#fff;cursor:pointer;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent;border:none;justify-content:center;align-items:center;gap:8px;margin-top:8px;font-weight:700;transition:background .1s,transform 80ms,opacity .15s;display:flex}.eq-numpad-action:active:not(:disabled){background:var(--color-primary-hover);transform:scale(.97)}.eq-numpad-action:disabled{opacity:.35;cursor:default}.eq-numpad-action--next{background:var(--color-primary)}.eq-numpad-action--next:active{background:var(--color-primary-hover)}@media print{.eq-explorer{display:none}.eq-print-note{text-align:center;color:#333;padding:.6in 0;font-size:13pt;display:block}}@media print{.colarith-item{border-bottom-color:#ddd}.colarith-problem{--colarith-cell-size:22px;font-size:18px}.colarith-line{border-top-color:#333}.colarith-blank{background:0 0;border-bottom-color:#555}}@media (width<=768px){.colarith-notebook .worksheet-header{height:auto;min-height:calc(4 * var(--nb-sq))}}@media print{.worksheet.colarith-notebook{--nb-sq:var(--nb-sq-print);--nb-gap:var(--nb-gap-print);--nb-offset:var(--nb-offset-print);padding:var(--nb-sq) var(--nb-sq) 0;min-height:calc(var(--nb-page-sq) * var(--nb-sq));overflow:visible}.colarith-notebook .worksheet-header{height:calc(3 * var(--nb-sq));background:#fff}.colarith-op{color:#111}.colarith-notebook .colarith-line:before{background:#333}}@media print{.colarith-item{border-bottom-color:#ddd}.colarith-problem{--colarith-cell-size:22px;font-size:18px}.colarith-line{border-top-color:#333}.colarith-blank{background:0 0;border-bottom-color:#555}}@media (width<=768px){.colarith-notebook .worksheet-header{height:auto;min-height:calc(4 * var(--nb-sq))}}@media print{.worksheet.colarith-notebook{--nb-sq:var(--nb-sq-print);--nb-gap:var(--nb-gap-print);--nb-offset:var(--nb-offset-print);padding:var(--nb-sq) var(--nb-sq) 0;min-height:calc(var(--nb-page-sq) * var(--nb-sq));overflow:visible}.colarith-notebook .worksheet-header{height:calc(3 * var(--nb-sq));background:#fff}.colarith-op{color:#111}.colarith-notebook .colarith-line:before{background:#333}}.colarith-grid{gap:14px 22px;display:grid}.colarith-item{border-bottom:1px solid var(--color-border-light);break-inside:avoid-page;page-break-inside:avoid;justify-content:center;align-items:center;min-height:128px;padding:8px 0;display:flex}.colarith-problem{--colarith-cell-size:24px;--colarith-cell-gap:2px;font-family:var(--font-figure);font-variant-numeric:tabular-nums;letter-spacing:0;flex-direction:column;align-items:flex-end;min-width:132px;font-size:20px;font-weight:600;line-height:1;display:inline-flex}.colarith-row{min-height:var(--colarith-cell-size);justify-content:flex-end;align-items:center;display:flex}.colarith-op{text-align:center;width:18px;color:var(--color-text);margin-right:6px;font-size:24px;line-height:1}.colarith-digit-row{grid-auto-flow:column;grid-auto-columns:var(--colarith-cell-size);column-gap:var(--colarith-cell-gap);justify-content:end;display:inline-grid}.colarith-cell{width:var(--colarith-cell-size);height:var(--colarith-cell-size);text-align:center;justify-content:center;align-items:center;display:inline-flex}.colarith-cell-empty{visibility:hidden}.colarith-line{border-top:2px solid var(--color-text);width:100%;margin:2px 0}.colarith-blank{width:calc(var(--colarith-cell-size) - 6px);height:calc(var(--colarith-cell-size) - 6px);border-bottom:2px solid var(--color-primary);background:var(--color-primary-faint);display:inline-block}@media print{.colarith-item{border-bottom-color:#ddd}.colarith-problem{--colarith-cell-size:22px;font-size:18px}.colarith-line{border-top-color:#333}.colarith-blank{background:0 0;border-bottom-color:#555}}.worksheet.colarith-notebook{--nb-sq:var(--nb-sq-screen);--nb-gap:var(--nb-gap-screen);--nb-offset:var(--nb-offset-screen);--notebook-grid-size:var(--nb-sq);padding:var(--nb-sq);overflow-x:auto}.colarith-notebook .worksheet-header{height:calc(3 * var(--nb-sq));margin:calc(-1 * var(--nb-sq)) calc(-1 * var(--nb-sq)) calc(var(--nb-header-gap,1) * var(--nb-sq));padding:0 var(--nb-sq);background:var(--color-surface);-webkit-print-color-adjust:exact;print-color-adjust:exact;border-bottom-width:2px;align-items:center;display:flex}.colarith-notebook .colarith-grid{grid-template-columns:repeat(var(--nb-cols), calc(var(--nb-cell-w) * var(--nb-sq)));column-gap:calc(var(--nb-gap) * var(--nb-sq));row-gap:calc(var(--nb-row-gap,1) * var(--nb-sq));margin-left:calc(var(--nb-offset) * var(--nb-sq));justify-content:start}.colarith-notebook .colarith-item{height:calc((var(--nb-rows) + 1) * var(--nb-sq));border:none;justify-content:flex-start;align-items:flex-end;min-height:0;padding:0}.colarith-notebook .colarith-problem{--colarith-cell-size:var(--nb-sq);--colarith-cell-gap:0px;min-width:0;font-size:calc(var(--nb-sq) * .77)}.colarith-notebook .colarith-row{height:var(--nb-sq);min-height:0}.colarith-notebook .colarith-op{width:var(--nb-sq);height:var(--nb-sq);font-size:calc(var(--nb-sq) * .9);justify-content:center;align-items:center;margin:0;display:inline-flex}.colarith-notebook .colarith-line{border:none;height:0;margin:0;position:relative}.colarith-notebook .colarith-line:before{content:"";background:var(--color-text);height:2px;position:absolute;top:-1px;left:0;right:0}.colarith-notebook .colarith-blank{width:calc(var(--nb-sq) - 6px);height:calc(var(--nb-sq) - 6px)}@media (width<=768px){.colarith-notebook .worksheet-header{height:auto;min-height:calc(4 * var(--nb-sq))}}@media print{.worksheet.colarith-notebook{--nb-sq:var(--nb-sq-print);--nb-gap:var(--nb-gap-print);--nb-offset:var(--nb-offset-print);padding:var(--nb-sq) var(--nb-sq) 0;min-height:calc(var(--nb-page-sq) * var(--nb-sq));overflow:visible}.colarith-notebook .worksheet-header{height:calc(3 * var(--nb-sq));background:#fff}.colarith-op{color:#111}.colarith-notebook .colarith-line:before{background:#333}}.colarith-notebook .coldiv-item{align-items:flex-start}.coldiv-problem{grid-template-columns:repeat(var(--cd-cols), var(--nb-sq));grid-template-rows:repeat(var(--cd-rows), var(--nb-sq));--colarith-cell-size:var(--nb-sq);font-family:var(--font-figure);font-size:calc(var(--nb-sq) * .77);font-variant-numeric:tabular-nums;letter-spacing:0;font-weight:600;line-height:1;display:grid;position:relative}.coldiv-quotient{grid-auto-flow:column;grid-auto-columns:var(--nb-sq);display:grid}.coldiv-rule{background:var(--color-text);-webkit-print-color-adjust:exact;print-color-adjust:exact;position:absolute}.coldiv-rule-v{left:calc(var(--cd-vx) * var(--nb-sq) - 1px);top:calc(var(--cd-vy0) * var(--nb-sq));width:2px;height:calc((var(--cd-vy1) - var(--cd-vy0)) * var(--nb-sq))}.coldiv-rule-h{left:calc(var(--cd-hx0) * var(--nb-sq));top:calc(var(--cd-hy) * var(--nb-sq) - 1px);width:calc((var(--cd-hx1) - var(--cd-hx0)) * var(--nb-sq));height:2px}@media print{.coldiv-rule{background:#333}}.order-grid{gap:6px 24px;display:grid;overflow-x:auto}.order-item{border-bottom:1px solid var(--color-border-light);font-family:var(--font-figure);letter-spacing:.3px;flex-wrap:nowrap;align-items:center;gap:10px;padding:8px 0;font-size:16px;font-weight:500;display:flex}.order-expr{white-space:nowrap;align-items:center;gap:5px;display:inline-flex}.order-expr .val{font-variant-numeric:tabular-nums}.order-expr .op{color:var(--color-text);font-weight:600}.order-paren{color:var(--color-text-muted);font-weight:600}.order-expr .order-paren+.val,.order-expr .val+.order-paren{margin-left:-3px}.order-boxes{--colarith-cell-size:24px;align-items:center;gap:4px;display:inline-flex}@media print{.order-grid{row-gap:0}.order-item{color:#111;border-bottom-color:#ddd;height:44px;padding:0}.order-expr .op,.order-paren{color:#111}.order-boxes{--colarith-cell-size:22px}}